Experimental and density functional theory investigation on one- and two-dimensional coordination polymers and their ZnO-doped nanocomposite materials for wastewater remediation

Two Cd(II) and Cu(II) coordination polymers (CPs) with the compositions of [Cd(HIPA)(HIZ)(H2O)2]n·3H2O (CP1) and [Cu(HIPA)(HIZ)2]n·2H2O∙MeOH (CP2), where, (H3IPA = 5-hydroxy isophthalic acid, and HIZ = imidazole), were successfully obtained by the reaction of the mixed ligand of H3IPA and HIZ under solvothermal conditions. The prepared CPs were characterized by X-ray diffractions (XRD), Fourier transform infrared (FTIR) spectroscopy, UV–visible spectroscopy, thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) analysis, and microscopic (TEM and SEM) techniques. The complexes 1 and 2 shows dual behavior as adsorbent and photocatalyst for the adsorption and photocatalytic degradation of methyl blue (MB), methyl orange (MO), and crystal violet (CV) dyes. Additionally, zinc-oxide doped composite materials ([email protected]1 and 2) were also synthesized using solvothermal and mechanochemical solid grinding methods. Compared with the parent coordination frameworks (CP1 and CP2), the composites ([email protected]1 and 2) exhibited slightly improved surface area with reduced photogenerated electron-hole ratio, hence displayed good photo degradation activity. Moreover, the density functional theory (DFT/B3LYP) with the counterpoise and dispersion corrections was employed to validate dyes adsorption mechanism with the reported CPs.